March 29, 2014 – The choice of ADP receptor inhibitor does not appear to affect bleeding risk, according to a study by DCRI Fellow Larry Jackson, MD.
Triple antiplatelet therapy with prasugrel or clopidogrel can increase the risk of bleeding in heart attack patients, but the relative risk “when going from to dual antiplatelet therapy to triple antithrombotic therapy is similar regardless of which drug is chosen, according to a study presented Saturday morning at the Scientific Sessions of the American College of Cardiology.
The study was conducted by the DCRI’s Larry Jackson, MD (pictured); Tracy Wang, MD, MHS, MSc; and colleagues from other institutions as part of the Treatment with ADP Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events after Acute Coronary Syndrome (TRANSLATE-ACS) project. TRANSLATE-ACS is a longitudinal, observational study of more than 12,000 heart attack patients treated with percutaneous coronary intervention (PCI) at 233 hospitals in the United States. Wang and DCRI Director Eric Peterson, MD, MPH, are the study’s principal investigators.
Dual antiplatelet therapy, which comprises aspirin and an adenosine diphosphate (ADP) receptor inhibitor, is the standard of care for most heart attack patients who have undergone PCI. Many of these patients, however, suffer from other conditions that require the use of an oral anticoagulant. The safety and efficacy of patients who receive triple therapy—aspirin, an ADP receptor inhibitor, and an anticoagulant—remain unclear. The arrival of newer ADP receptor inhibitors such as prasugrel, which have begun to challenge the dominance of the older clopidogrel, has led to additional uncertainty.
In this study, Jackson and his colleagues sought to determine the prevalence of triple therapy with either ADP receptor inhibitor, compare the outcomes and characteristics of patients who received triple therapy with either anticoagulant to those who received dual therapy, and compare the clinical characteristics and outcomes between patients receiving triple antithrombotic therapy with clopidogrel versus those receiving prasugrel.
Using data from the TRANSLATE-ACS registry, the researchers looked at 11,757 heart attack patients from 233 hospitals across the United States. Patients were divided into four study groups: dual therapy with aspirin and clopidogrel; dual therapy with aspirin and prasugrel; triple therapy with aspirin, an anticoagulant, and clopidogrel; and triple therapy with aspirin, and anticoagulant, and prasugrel.
They found that triple therapy was associated with a higher overall bleeding risk regardless of which ADP receptor inhibitor was used. There were no significant differences in the rate of major adverse cardiac events between the study groups. The researchers also found that use of prasugrel has increased among heart attack patients.
These findings, Jackson said, suggest that clinicians should weigh their options carefully when choosing a therapy for their patients.
“If you have a patient with no history of stroke or major bleeding, prasugrel is an agent you should consider, but only under the right circumstances,” he said.